The direct conversion of various carboxylic acids, that include stericallyhindered amino acids and di-peptides, to O-benzyl hydroxamates is demonstrated using sulfonate esters of benzotriazoles under ambient and milder conditions without significant racemization. This simple and efficient protocol is extended to the synthesis of O-benzyl hydroxamates, using in situ generated solid supported TsOBt
Sulfonamide synthesis using N-hydroxybenzotriazole sulfonate: an alternative to pentafluorophenyl (PFP) and trichlorophenyl (TCP) esters of sulfonic acids
作者:Nani Babu Palakurthy、Bhubaneswar Mandal
DOI:10.1016/j.tetlet.2011.10.107
日期:2011.12
The N-hydroxybenzotriazole (HOBt) sulfonate esters undergo amidation under ambient conditions in the presence of di-isopropylethyl amine. This method can be applied to varieties of amines including sterically hindered amino acid esters in less time with reasonably good yields.HOBt ester of sulfonic acids can be a replacement for pentafluorophenyl and trichlorophenyl ester as well as chloride moiety of sulfonyl chloride for amidation. (C) 2011 Elsevier Ltd. All rights reserved.
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